... .Grade:10#, 20#, 45#, 16Mn, A53(A,B) 3.OD:21.3--457mm 4.WT:2.77-45.24mm 5.Brand ... , shipbuilding, fertilizer equipment and pipeline, structure, petrochemical, pharmaceutical industrySurface Black painting, varnish paint, anti rust oil, hot galvanized, cold galvanized, 3PE ...